An amber heat health alert has now been issued for most of England, as soaring temperatures could pose a risk to vulnerable groups.
Temperatures across the country continue to rise amid an unexpected September heatwave, with the Met Office predicting highs of 33C later this week.
After initially issuing a yellow heat-health alert for most of the UK except the northeast, the UK Health Security Agency (UKHSA) on Tuesday upgraded it to an amber alert.
A yellow alert is now in place in the northeast as well.
The amber heat health alert, which signifies an increased risk to people above the age of 65 and those with pre-existing health conditions, will be in force from midday on Tuesday 5 September until 9pm on Sunday 10 September.
According to the Met Office’s official guidance, an amber alert indicates a situation in which the “expected impacts are likely to be felt across” the healthcare system, including an “observed increase in mortality” among vulnerable groups.
The weather service said there’s a possibility the highest temperature of 2023 – on 10 June when the mercury hit 32.2C – could be exceeded this week, “most likely in the southeast where one or two places could see 33C”.
It is expected to be 4C hotter in the UK than Ibiza this week, with maximum temperatures also higher than those forecast for Ayia Napa and Athens in Greece.
The Met Office on Monday warned that it will remain “uncomfortably warm overnight” through this week.
In a post on X, formerly Twitter, the weather service said: “In addition to high daytime temperatures through this week, it will remain uncomfortably warm overnight.
“There is a chance of some tropical nights, especially in the south, which is when overnight temperatures remain in excess of 20C.”
Heatwave criteria will likely be met in a number of places over the next couple of days, and for much of the UK it will feel “very warm to hot”, Rachel Ayers, senior meteorologist at the Met Office, said.